﻿
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<!-- saved from url=(0014)about:internet -->
<html xmlns:msxsl="urn:schemas-microsoft-com:xslt" xmlns:mssdk="winsdk" xmlns:script="urn:script" xmlns:build="urn:build" xmlns:MSHelp="http://msdn.microsoft.com/mshelp">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
<meta name="Description" content="The NO_MORE_SYSTEM_PTES bug check has a value of 0x0000003F. This is the result of a system which has performed too many I/O actions. This has resulted in fragmented system page table entries (PTE)."/>
<meta name="MSHAttr" content="PreferredSiteName:MSDN"/>
<meta name="MSHAttr" content="PreferredLib:/library/windows/hardware"/>
<title>Bug Check 0x3F: NO_MORE_SYSTEM_PTES</title>

<meta name="MS-HAID" content="t04_bugs_00_f514d83b-7493-4721-bd31-1178e5aaa45a.xml"/>


<link rel="STYLESHEET" type="text/css" HREF="../common/backsdk4.css"/>





<style>
html,div { margin: 0; padding: 0;}

body {
	padding: 0px;
	margin: 0px;
	overflow: auto;
	height: 100%;
}

#winchm_template_button{
	float: right;
	width: 93px;
	top: 7px;
	position: relative;
	text-align: right;
	right: 5px;
	height: auto;
}

#winchm_template_top{
	padding: 0px;
	margin: 0px;
	border-bottom: 1px solid #9B9B9B;
	background-color: #B1CEFE;
}

#winchm_template_navigation{
	margin: 0px;
	padding-top: 7px;
	padding-left: 7px;
	padding-bottom: 3px;
	padding-right: 0px;
	font-size: 8.5pt;
	font-family: Arial, Helvetica, sans-serif;
	font-weight: normal;
	color: #585858;
}

#winchm_template_title{
	margin: 0px;
	padding-top: 4px;
	padding-left: 7px;
	padding-bottom: 7px;
	padding-right: 0px;
	font-size: 18px; 
	font-family: Verdana, Geneva, sans-serif;
	color: #363636;
}

#winchm_template_content{
	margin-top: 20px;
	margin-left: 15px;
	margin-bottom: 20px;
	margin-right: 15px;
	width: auto  !important;
	width: 100%;
}

#winchm_template_footer{
	border-width: 1px;
	border-color: #B1CEFE;
	border-top-style: solid;
	margin-top: 15px;
	margin-left: 15px;
	margin-bottom: 20px;
	margin-right: 15px;
	padding-top: 7px;
	padding-left: 0px;
	padding-bottom: 0px;
	padding-right: 0px;
	font-family: arial, helvetica, sans-serif;
	font-size: 8.5pt;
	color: #696969;
	width: auto;
	text-align: left;
}


#winchm_template_container{
	margin: 0px;
	padding: 0px;
	position: static;
	padding-bottom: 3px;
	overflow: auto;
	background-color: #FFFFFF;
}


@media print
{
#winchm_template_container{
	position: static;	
	margin: 0px;
	padding: 5px;
	
	width: auto;
	height: auto;
	overflow: auto;
}
#winchm_template_button{
visibility:hidden;
}
}

#winchm_template_navigation A:link	{text-decoration: none; color:#004080}
#winchm_template_navigation A:visited  {text-decoration: none; color: #004080}
#winchm_template_navigation A:active {text-decoration: none; color: #004080 }
#winchm_template_navigation A:hover {text-decoration: none;color: #0080FF}

A:link	{text-decoration: underline; color:#0033CC}
A:visited  {text-decoration: underline; color: #0033CC}
A:active {text-decoration: underline; color: #0033CC }
A:hover {text-decoration: underline;color: #FF0000;}
</style>
<script type="text/javascript">
function isMobile(){
Agent = window.navigator.userAgent;
if (Agent.indexOf("iPhone")>=1 || Agent.indexOf("iPad")>=1 || Agent.indexOf("iPod")>=1 || Agent.indexOf("Android")>=1){
return true;
}else{
return false;	
}

}
function d_onresize(){
if (window.navigator.userAgent.indexOf("MSIE")>=1){
document.getElementById('winchm_template_container').style.pixelWidth = document.body.offsetWidth - 3;
document.getElementById('winchm_template_container').style.pixelHeight = document.body.offsetHeight - document.getElementById('winchm_template_top').offsetHeight - 4;
}
document.getElementById('winchm_template_container').style.top = document.getElementById('winchm_template_top').offsetHeight + 'px';
}

function d_onbeforeprint(){
document.getElementById('winchm_template_container').style.width = 'auto';
document.getElementById('winchm_template_container').style.height = 'auto';
}

function d_onafterprint(){
d_onresize();
}

if(!isMobile()){

window.onload = d_onresize;
window.onresize = d_onresize;
window.onbeforeprint = d_onbeforeprint;
window.onafterprint = d_onafterprint;

document.write("<style>\n");
document.write("body {overflow: hidden;}\n");
document.write("#winchm_template_container {position: absolute;overflow: auto;top : 0px;right: 0px;bottom: 0px;left: 0px;}\n");
document.write("</style>\n");
}

</script>
</head>
<body><script language="JavaScript" type="text/JavaScript">
function syn(){
if(parent.nav.tree){
 if(parent.nav.tree.loaded){
  parent.nav.tree.selectNode(1655);
 }else{
  setTimeout("syn()",500);
}
  }else{
  setTimeout("syn()",500);
  }}
if(parent!=self){
  setTimeout("syn()",100);
}else{
  parent.location.href = "../../index.htm?page=debugger/bug_check_0x3f__no_more_system_ptes.htm";
}
originalOnload = window.onload;
if(originalOnload==null){
window.onload = function(){parent.contentLoaded = true;};
}else{
window.onload = function(){originalOnload();parent.contentLoaded = true;};
}
</script> 


<div id="winchm_template_top">
	<div id="winchm_template_button"><A href="bug_check_0x3e__multiprocessor_configuration_not_supported.htm" title="Previous topic"><img id="winchm_template_prev" alt="Previous topic" src="../template2/btn_prev_n.gif" border="0"></a><A href="bug_check_0x40__target_mdl_too_small.htm" title="Next topic"><img id="winchm_template_next" alt="Next topic" src="../template2/btn_next_n.gif" border="0"></a></div>
	<div id="winchm_template_navigation">Help &gt; 
<A href="introduction6.htm">Debugging Tools for Windows (WinDbg, KD, CDB, NTSD)</A> &gt; <A href="bug_checks__blue_screens_.htm">Bug Checks (Blue Screens)</A> &gt; <A href="bug_check_code_reference2.htm">Bug Check Code Reference</A> &gt; </div>
	<div id="winchm_template_title">Bug Check 0x3F: NO_MORE_SYSTEM_PTES</div>
</div>
<div id="winchm_template_container">
	<div id="winchm_template_content"><div id="mainSection"><p>The NO_MORE_SYSTEM_PTES bug check has a value of 0x0000003F. This is the result of a system which has performed too many I/O actions. This has resulted in fragmented system page table entries (PTE).</p>
<p>
<div class="alert"><b>Important </b>This topic is for programmers. If you are a customer who has received a blue screen error code while using your computer, see 
            <a href="http://windows.microsoft.com/en-us/windows-10/troubleshoot-blue-screen-errors" xmlns:loc="http://microsoft.com/wdcml/l10n">Troubleshoot blue screen errors</a>.</div>
</p>
<h2> NO_MORE_SYSTEM_PTES Parameters</h2>
<p>The following parameters are displayed on the blue screen.</p>
<table>
<tr>
<th>Parameter</th>
<th>Description</th>
</tr>
<tr>
<td>
<p>1</p>
</td>
<td>
<p><b>0:</b> system expansion PTE type</p>
<p><b>1:</b> nonpaged pool expansion PTE type</p>
</td>
</tr>
<tr>
<td>
<p>2</p>
</td>
<td>
<p>Size of memory request</p>
</td>
</tr>
<tr>
<td>
<p>3</p>
</td>
<td>
<p>Total free system PTEs</p>
</td>
</tr>
<tr>
<td>
<p>4</p>
</td>
<td>
<p>Total system PTEs</p>
</td>
</tr>
</table>
<p> </p>
<h2>Cause</h2>
<p>In almost all cases, the system is not actually out of PTEs. Rather, a driver has requested a large block of memory, but there is no contiguous block of sufficient size to satisfy this request.</p>
<p>Often video drivers will allocate large amounts of kernel memory that must succeed. Some backup programs do the same.</p>
<h2>Resolution</h2>
<p><b>A possible work-around:  </b>Modify the registry to increase the total number of system PTEs. If this does not help, remove any recently-installed software, especially backup utilities or disk-intensive applications.</p>
<p><b>Debugging the problem:</b> The following method can be used to debug bug check 0x3F. </p>
<p>First, get a stack trace, and use the <a href="#Bookmark2442"><b>!sysptes 3</b></a> extension command.</p>
<p>Then set <b>HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\TrackPtes</b> equal to DWORD 1, and reboot. This will cause the system to save stack traces. </p>
<p>This allows you to display more detailed information about the PTE owners. For example:</p>
<pre class="syntax" xml:space="preserve"><code>0: kd&gt; !sysptes 4

0x2c47 System PTEs allocated to mapping locked pages

VA       MDL     PageCount  Caller/CallersCaller
f0e5db48 eb6ceef0        1 ntkrpamp!MmMapLockedPages+0x15/ntkrpamp!IopfCallDriver+0x35
f0c3fe48 eb634bf0        1 netbt!NbtTdiAssociateConnection+0x1f/netbt!DelayedNbtProcessConnect+0x17c
f0db38e8 eb65b880        1 mrxsmb!SmbMmAllocateSessionEntry+0x89/mrxsmb!SmbCepInitializeExchange+0xda
f8312568 eb6df880        1 rdbss!RxCreateFromNetRoot+0x3d7/rdbss!RxCreateFromNetRoot+0x93
f8363908 eb685880        1 mrxsmb!SmbMmAllocateSessionEntry+0x89/mrxsmb!SmbCepInitializeExchange+0xda
f0c54248 eb640880        1 rdbss!RxCreateFromNetRoot+0x3d7/rdbss!RxCreateFromNetRoot+0x93
f0ddf448 eb5f3160        1 mrxsmb!MrxSmbUnalignedDirEntryCopyTail+0x387/mrxsmb!MRxSmbCoreInformation+0x36
f150bc08 eb6367b0        1 mrxsmb!MrxSmbUnalignedDirEntryCopyTail+0x387/mrxsmb!MRxSmbCoreInformation+0x36
f1392308 eb6fba70        1 netbt!NbtTdiOpenAddress+0x1fb/netbt!DelayedNbtProcessConnect+0x17c
eb1bee64 edac5000      200 VIDEOPRT!pVideoPortGetDeviceBase+0x118/VIDEOPRT!VideoPortMapMemory+0x45
f139b5a8 edd4b000       12 rdbss!FsRtlCopyWrite2+0x34/rdbss!RxDriverEntry+0x149
eb41f400 ede92000       20 VIDEOPRT!pVideoPortGetDeviceBase+0x139/VIDEOPRT!VideoPortGetDeviceBase+0x1b
eb41f198 edf2a000       20 NDIS!NdisReadNetworkAddress+0x3a/NDIS!NdisFreeSharedMemory+0x58
eb41f1e4 eb110000       10 VIDEOPRT!pVideoPortGetDeviceBase+0x139/VIDEOPRT!VideoPortGetDeviceBase+0x1b
......</code></pre>
<p>If the system runs out of PTEs again after the <b>TrackPtes</b> registry value has been set, <a href="#Bookmark1780"><b>bug check 0xD8</b></a> (DRIVER_USED_EXCESSIVE_PTES) will be issued instead of 0x3F. The name of the driver causing this error will be displayed as well.</p></div></div>	
	<div id="winchm_template_footer">Copyright &copy; 2019. All rights 
reserved. (To change the copyright info, just edit it in template.)</div>
</div>

</body>
</html>
